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Why did powdered aluminum become an adhesive?

Q. Baking soda [on eBay or Amazon] and water and it started to bubble, then it turned as hard a as a rock, does any one have any ideas why this happened, because it also worked as an adhesive, and will not move, its stuck on my work table, any help please on what happened, why it happened, and how I get it off my desk, thanks.

Christopher Newomen
electronics designer - Oshawa, Ontario, Canada
2004

The other day at work, I was trying to make a combination of powdered aluminum and

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2004

Try more baking soda.

Khair Shishani
aircraft maintenance - Al Ain, UAE

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Aluminum is highly reactive with Oxygen. Had you mixed the powdered aluminum with powdered Iron oxide and started the reaction you would have gotten the thermite reaction which produces molten iron. Baking soda (NaHCO₃) added to Aluminum powder (Al) in water (H₂O) probably bubbled off the Hydrogen and left some aluminum oxide (which I think is also known as carborundum)and sodium oxide. A chemist would be able to give you the exact reaction. As for getting it off of your bench, a diamond blade should be able to grind it off.

John Smit
- Reno, Nevada
2004